Loss of connectivity - every few days

I have problems with two Windows 7 x64 machines - every few days they lose internet/network connection, though my Windows XP x32 and Linux x64 machines do not have any such problems. Since I had problems with ZoneAlarm on the Windows 7 machines initially (screen kept freezing every day or so), until I updated to 9.3.037.000, I wonder whether ZoneAlarm may be causing this issue (note all the Win XP and Win 7 machines are using ZA Internet Security 9.3.037.000).

Notes: The router is a Billion 7800N. The network is CAT6 wired throughout (no wireless use). The 7800N is linked to a Netgear GS724T smart switch along with all the PC’s and other devices on the network.

When the issue occurs, the Windows 7 machine cannot see the internet via IE8, local VNC does not work, yet I can ping other machines on the network and various websites(?). If I let Windows 7 try to troubleshoot the problem, I get the following message; "Your computer appears to be configured correctly ......".

If I disable the network adapter and re-enable, the problem is not rectified.
The only way I have been able to get round the problem so far is to reboot the PC’s – this is not acceptable as the machines are all required for 24/7 use.

Re: Loss of connectivity - every few days

Considering you are a long time user of ZA you should already know the basics for issues of this kind.

Considering that you don't get connected even by disabling the network card then it is unlikely due to ZA.

Anyway, as usual ensure your router IP is set to TRUSTED on the ZA firewall section --> zones and that your DNS and DHCP IP ddresses are set to TRUSTED too. Ensure that your ZA trusted zone is set to MEDIUM and not HIGH. Double check that IPv6 support in ZA is CHECKED (advanced option of the ZA firewall section). You must find a 'localhost' (127.0.0.1) entry in the firewall zone set to TRUSTED too.

Re: Loss of connectivity - every few days

Thanks for the post.

I think I have the pointers set as suggested;

1. Router IP is set to TRUSTED - Yep.
2. DNS and DHCP IP addresses are set to TRUSTED - DHCP Yep, Don't have one for DNS listed .....
3. Ensure that your ZA trusted zone is set to MEDIUM and not HIGH - Yep.
4. Double check that IPv6 support in ZA is CHECKED - Yep
5. 'localhost' (127.0.0.1) entry in the firewall zone set to TRUSTED - there is 'Loopback adapter' on this IP.

I'm waiting on a response from the modem/router manufacturer to find if the issue lies here .....